Pteranodon

Pteranodon (/təˈrænədɒn/; from Ancient Greek pteron 'wing', an- 'without', and odon 'tooth') is a genus of pterosaur. It was one of the largest flying reptiles. The biggest kind, P. longiceps, had a wingspan of over 6 m (20 ft). They lived during the late Cretaceous in North America. We find their fossils in places like Kansas, Nebraska, Wyoming, South Dakota, and Alabama.

More fossil pieces of Pteranodon have been found than any other pterosaur. Scientists know of about 1,200 specimens, many with almost full skulls and skeletons.

When the first fossils were found, they were grouped with toothed pterosaurs like Ornithocheirus and Pterodactylus. In 1876, Othniel Charles Marsh saw it was different. He noted it had no teeth, which was unique for pterosaurs at that time.

Pteranodon belongs to the family Pteranodontidae. It is part of the clade Pteranodontia, which also includes nyctosaurids. Scientists have found two types of Pteranodon specimens. These may be males and females. They differed in size and crest shape. Males could have wingspans from 5.6 to 7.6 m (18 to 25 ft). Females were smaller, averaging about 3.8 m (12 ft).

Discovery and history

Pteranodon was the first pterosaur found outside of Europe. Its fossils were first discovered by Othniel Charles Marsh in 1870 or 1871 in the Late Cretaceous Smoky Hill Chalk deposits of western Kansas. These fossils included partial wing bones and a tooth from a prehistoric fish, which Marsh thought belonged to the pterosaur at first. He named the find Pterodactylus oweni but later changed it to Pterodactylus occidentalis after realizing the name was already used.

The first Pteranodon skull was found in 1876 by Samuel Wendell Williston along the Smoky Hill River in Wallace County, Kansas, USA. This skull showed that these pterosaurs were different from European species because they had no teeth and had bony crests. Marsh recognized this major difference and created the name Pteranodon, meaning "wing without tooth," in 1876. He reclassified all the North American species under this new name.

Description

Adult male Pteranodons were very large flying reptiles. They were among the biggest animals to ever fly. An average adult male had a wingspan of about 5.6 m (18 ft). Females were smaller, with a wingspan of about 3.8 m (12 ft). One very big Pteranodon named Pteranodon longiceps had a wingspan of over 6 m (20 ft).

Pteranodons had beaks without teeth, which is different from earlier flying reptiles. Their beaks were long and ended in sharp points. The most noticeable feature was the crest on top of their heads. Males had large, narrow crests. Females had smaller, rounded crests. These crests were probably used to show off.

Paleobiology

Pteranodon likely flew like a modern-day albatross. It used a flight pattern called "dynamic soaring" to travel far without flapping its wings. It could flap its wings for short bursts of speed. Pteranodon probably took off by leaping into the air using its strong forelimbs.

Pteranodon mainly ate fish. They likely caught fish by dipping their long beaks into the water while swimming, not while flying. The large crest on its skull was probably used for showing off, especially during mating. The crests varied in size and shape between males and females. Larger Pteranodon specimens had bigger crests.

Paleoecology

Main articles: Niobrara Formation and Western Interior Seaway

Pteranodon fossils have been found in places like the Smoky Hill Chalk and the Pierre Shale Formation. Long ago, this area was covered by a big inland sea called the Western Interior Seaway. These rock layers stretch from Kansas in the United States up to Manitoba in Canada, but Pteranodon fossils are only found as far north as South Dakota.

Pteranodon flew in the skies with other flying reptiles like Nyctosaurus and birds such as Ichthyornis. The oceans below had many sea creatures, including ammonites, squid, sea turtles, plesiosaurs like Elasmosaurus and Styxosaurus, and large marine reptiles called mosasaurs. Some of these sea animals might have eaten Pteranodon.

Classification

Pteranodon fossils come from the Niobrara Formation in the central United States. They lived during the Santonian stage of the Cretaceous period, around 88 to 78 million years ago. Scientists have found about 1,200 fossils of Pteranodon, many with good skulls and skeletons.

Researchers think there are two kinds of Pteranodon: Pteranodon longiceps and Pteranodon sternbergi. The main difference is the shape of the crest on the heads of adult males. Because skull fossils are rare, scientists look at the rock layer where a fossil is found to help identify the kind. P. sternbergi had an upright crest and is older, while P. longiceps lived later.